JP2023536175A - ELASTICITY MEMBER AND DISPLAY DEVICE HAVING THE SAME - Google Patents

Abstract

The elastic member according to the embodiment is an elastic member including a first region and a second region, wherein the elastic member has a surface roughness having a longitudinal direction, and the first region is defined as a folding region. , the second region is defined as an unfolding region, a first pattern portion having a long direction and a short direction is formed in the first region of the elastic member, and the long direction of the first pattern portion and the surface The longitudinal direction of roughness is different.

Description

Embodiments relate to an elastic member and a display device including the same.

Recently, there is an increasing demand for a flexible or foldable display device that can easily carry various applications and display images on a larger screen while being carried.

Such a flexible or foldable display can be folded or partially bent when carried or stored, and can be unfolded when displaying an image. As a result, the image display area can be increased and the user's portability can be facilitated.

Such a flexible or foldable display device is repeatedly subjected to a restoration process of unfolding after being folded or bent.

That is, since the flexible or foldable display device undergoes repeated folding and unfolding operations, the substrate of the flexible display device is required to have a certain degree of strength and elasticity so that the substrate is not cracked or deformed during folding and restoration. should not occur.

Meanwhile, a display substrate, which is an elastic member constituting a flexible or foldable display device, undergoes a pretreatment process of rolling the substrate for flexible or foldable characteristics.

Surface roughness is formed on the surface of the elastic member through the rolling process, and the elastic member has different physical properties depending on the direction in which the surface roughness is formed.

Therefore, there is a need for an elastic member with a new structure that can secure folding characteristics and reliability in the elastic member having different physical characteristics depending on the direction.

Embodiments seek to provide elastic members with improved folding properties and reliability.

An elastic member according to an embodiment is an elastic member including a first region and a second region, wherein the elastic member has a surface roughness having a longitudinal direction, and the first region is defined as a folding region. , the second region is defined as an unfolding region, a first pattern portion having a long direction and a short direction is formed in the first region of the elastic member, the long direction of the first pattern portion and the surface The longitudinal direction of roughness is different.

In the elastic member according to the embodiment, the hole- or groove-shaped pattern portion formed in the elastic member can be formed along the longitudinal direction of the surface roughness of the elastic member.

Specifically, the long direction of the pattern portion can be formed in a direction different from the longitudinal direction of the surface roughness. That is, the long direction of the pattern portion is arranged closer to the vertical direction than the horizontal direction to the longitudinal direction of the surface roughness.

Accordingly, it is possible to improve the folding property caused by the difference in physical property between the moving direction and the vertical direction of the roller formed on the surface of the elastic member during the rolling process.

That is, by forming the long direction of the pattern portion in a direction substantially perpendicular to the longitudinal direction of the surface roughness, which is a direction similar to the vertical direction, the pattern portion remains on the elastic member after forming the pattern portion. The surfaces may be such that more of the surface in the direction of travel of the roller remains than the surface in the vertical direction.

As a result, more surfaces in the moving direction of the roller, which have a larger elastic modulus than the surfaces in the vertical direction, remain, thereby minimizing plastic deformation due to stress generated when the elastic member is folded or restored.

Accordingly, plastic deformation that occurs when the elastic member is folded can be minimized, thereby improving folding characteristics and reliability of the elastic member.

It is a drawing illustrating a perspective view of an elastic member according to an embodiment.

It is a drawing illustrating a perspective view of an elastic member according to an embodiment.

FIG. 4 is a side view of an elastic member before folding according to an embodiment; FIG.

FIG. 4 is a side view of an elastic member after being folded according to an embodiment; FIG.

FIG. 4 is a drawing illustrating a top view of a first surface of an elastic member according to an embodiment; FIG.

FIG. 10 is a top view of the second surface of the elastic member according to the embodiment; FIG.

FIG. 4 is a drawing for explaining that a rolling process is performed on the elastic member according to the embodiment; FIG.

FIG. 4 is a drawing for explaining the direction of surface roughness formed on an elastic member according to an example; FIG.

FIG. 4 is a drawing showing an enlarged view of one region of the elastic member according to the embodiment; FIG.

FIG. 11 is a drawing illustrating a top view of a first surface of an elastic member according to another embodiment; FIG.

4A and 4B are diagrams illustrating various cross-sectional views according to layer structures of various elastic members according to an embodiment;

4A and 4B are diagrams illustrating various cross-sectional views according to layer structures of various elastic members according to an embodiment;

4A and 4B are diagrams illustrating various cross-sectional views according to layer structures of various elastic members according to an embodiment;

4A and 4B are diagrams illustrating various cross-sectional views according to layer structures of various elastic members according to an embodiment;

It is drawing for demonstrating the example of application of the elastic member which concerns on an Example.

Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the technical concept of the present invention is not limited to the described embodiments, and can be embodied in various forms. One or more of the components can be selectively used in combination or replacement. Moreover, terms (including technical and scientific terms) used in the embodiments of the present invention are commonly understood by one of ordinary skill in the art to which the present invention pertains, unless explicitly defined otherwise. Commonly used terms, such as those defined in dictionaries, taken to mean possible, could be interpreted in the light of the contextual meaning of the technology involved.

Also, the terms used in the embodiments of the present invention are for the purpose of describing the embodiments and are not intended to limit the present invention. In this specification, the singular can also include the plural unless otherwise specified in the description, and when "at least one (or one or more) of A, B, and C" is described, A, B , C can include one or more of all possible combinations.

Also, terms such as first, second, A, B, (a), and (b) can be used in the description of the constituent elements of the embodiments of the present invention. Such terms are used to distinguish the component from other components, and are not intended to limit the nature, order, or the like of the component.

and when a component is described as being “coupled”, “coupled” or “connected” to another component, that component is directly linked or connected to the other component; It includes all cases where another component is "coupled", "coupled" or "connected" between each component.

Also, when described as being formed or positioned “above or below” each component, “above or below” includes not only the case where the two components are in direct contact, but also one or more other components. It also includes when a component is formed or positioned between two components.

In addition, the expression 'up or down' may include not only the upward direction but also the downward direction with respect to one component.

Hereinafter, elastic members according to examples will be described with reference to the drawings.

FIG. 1 is a drawing illustrating a perspective view of a display device including an elastic member according to an embodiment. A display device according to an embodiment is a flexible display device or a foldable display device that can be bent in one direction.

Referring to FIG. 1 , a display apparatus 1000 according to an embodiment may include an elastic member 100 , a display panel 200 arranged on the elastic member 100 , and a touch panel 300 arranged on the display panel 200 . .

The elastic member 100 may support the display panel 200 and the touch panel 300 . That is, the elastic member 100 may be a support substrate that supports the display panel 200 and the touch panel 300 .

Meanwhile, the touch panel 300 may be integrally formed with the display panel 200 . For example, the touch panel 300 may be integrated with the display panel 200 in an on-cell or in-cell manner.

The elastic member 100 may include metal material. For example, the elastic member 100 may include metal, metal alloy, plastic, composite material (eg, carbon fiber reinforced plastic, magnetic or conductive material, glass fiber reinforced material, etc.), ceramics, sapphire, glass, and the like. For example, the elastic member 100 may include SUS.

The elastic member 100 may be formed of a single layer or may be formed of multiple layers.

The elastic member 100 may be flexible or foldable. That is, the elastic member 100 can bend or bend in one direction. That is, the elastic member 100 is a display substrate applied to a flexible display device or a foldable display device.

The elastic member 100 defines a first direction 1D and a second direction 2D different from the first direction 1D. For example, the first direction 1D may be defined as the same direction as the folding axis direction of the elastic member 100, and the second direction may be perpendicular to the first direction.

One of the first direction 1D and the second direction 2D may be defined as the width direction of the elastic member 100, and the other direction may be defined as the longitudinal direction of the elastic member 100. good.

The elastic member 100 may be folded using one of the width direction and the longitudinal direction of the elastic member 100 as a folding axis.

Hereinafter, for convenience of explanation, the first direction is defined as the same direction as the folding axis. Also, the first direction is defined as the width direction of the elastic member 100 and the second direction is defined as the longitudinal direction of the elastic member 100 .

The elastic member 100 may include at least two regions. Specifically, the elastic member 100 may include a first region 1A and a second region 2A.

The first area 1A may be defined as an area where the elastic member 100 is folded. That is, the first area 1A is a folding area.

Also, the second region 2A may be defined as a region where the elastic member 100 is not folded. That is, the second area 2A is an unfolding area.

The first area 1A and the second area 2A will be described in detail below.

The display panel 200 is arranged on the elastic member 100 .

The display panel 200 may include a plurality of pixels including a switching thin film transistor, a driving thin film transistor, a storage device and an organic light emitting diode (OLED). Organic light emitting diodes can be deposited at relatively low temperatures, and are mainly applied to flexible display devices due to their low power consumption and high brightness. Here, a pixel is the minimum unit for displaying an image, and the display panel displays an image through a plurality of pixels.

The display panel 200 may include a substrate, gate lines disposed on the substrate, and data lines and common power lines that insulate and cross the gate lines. Generally, one pixel is defined by a gate line, a data line and a common power line.

The substrate may include a flexible material such as a plastic film, and the display panel 200 is implemented by arranging organic light emitting diodes and pixel circuits on the flexible film.

The touch panel 300 is arranged on the display panel 200 . The touch panel 300 can implement a touch function in a foldable display device or a flexible display device. In a foldable display device or a flexible display device that simply displays images without a touch function, the touch panel is omitted. good too.

The touch panel 300 can include a substrate and touch electrodes disposed on the substrate. The touch electrode may sense the position of the input device that touches the foldable display device or the flexible display device by a capacitive method or a resistive film method.

A substrate of the touch panel 300 may include a flexible material such as a plastic film, and the touch panel 300 is implemented by arranging touch electrodes on a flexible film.

As described above, when the touch panel 300 is integrally formed with the display panel 200, the substrate of the touch panel 300 may be the substrate of the display panel or a part of the display panel. Accordingly, the touch panel 300 and the display panel 200 can be integrally formed, and the thickness of the display device can be reduced.

Meanwhile, the elastic member 100 and the display panel 200 may have different sizes.

For example, the area of the elastic member 100 may be between 90% and 110% of the area of the display panel 200 . Specifically, the area of the elastic member 100 may be 95% to 105% of the area of the display panel 200 . More specifically, the area of the elastic member 100 may be between 97% and 100% of the area of the display panel 200 .

When the area of the elastic member 100 is less than 90% of the area of the display panel 200, the support force of the elastic member 100 to support the display panel 200 or the touch panel 300 is reduced, and the unfolding area of the elastic member 100 is reduced. A curl phenomenon or the like may occur. As a result, when the user views the screen area, the visibility is reduced, and when the touch is driven, the screen of the touch area is imperfect due to the curl area, which may cause a touch malfunction.

In addition, when the area of the elastic member 100 exceeds 110% of the area of the display panel 200, although the elastic member 100 secures a supporting force for supporting the display panel or the touch panel, The bezel area of the display device including the display panel and the touch panel is increased. As a result, a wide effective screen area cannot be provided to the user, thereby causing inconvenience in using the display apparatus.

Meanwhile, although not shown in the drawings, a cover window for protecting the foldable display device or the flexible display device is additionally arranged above the touch panel 300 or above the display panel 200 (if the touch panel is omitted). may be

Meanwhile, the elastic member 100, the display panel 200, and the touch panel 300 may be adhered by an adhesive layer or the like.

As mentioned above, the display device includes the elastic member 100 .

Referring to FIG. 2, the elastic member 100 can bend in one direction.

Specifically, the elastic member 100 may include a first surface 1S and a second surface 2S opposite to the first surface 1S. The elastic member 100 may be bent such that the first surface 1S or the second surface 2S faces each other. That is, the surfaces on which the panels are arranged may be bent to face each other, or the surfaces opposite to the surfaces on which the panels are arranged may be bent to face each other.

However, embodiments are not limited to this, and the elastic member 100 may be curved such that the second surface and the first surface are alternately opposed to each other. That is, the elastic member 100 may include multiple first regions and multiple second regions.

In the following description, as shown in FIG. 2, the first surface 1S of the elastic member 100 is bent in the direction facing each other.

As I mentioned earlier. The elastic member 100 defines a first area 1A and a second area 2A. The first area 1A and the second area 2A are areas defined when the elastic member 100 is bent in a direction in which the first surfaces 1S face each other.

Specifically, the elastic member 100 bends in one direction, and the elastic member 100 is divided into a first region 1A that is a folding region and a second region 2A that is a non-folding region. classified.

Referring to FIGS. 3 and 4, the elastic member 100 may include a first region 1A, which is the region where the elastic member 100 bends. In addition, the elastic member 100 does not bend and may include a second region 2A arranged adjacent to the first region 1A.

For example, the second regions 2A are formed on the left and right sides of the first region 1A with respect to the direction in which the elastic member 100 bends. That is, the second regions 2A are arranged at both ends of the first region 1A. That is, the first region 1A is arranged between the second regions 2A.

The embodiment is not limited to this, and the first region 1A is further formed outside the second region 2A.

The first region 1A and the second region 2A are formed on the same elastic member 100. As shown in FIG. That is, the first area 1A and the second area 2A are integrally formed without being separated from the same single elastic member 100. As shown in FIG.

The sizes of the first region 1A and the second region 2A may be different. Specifically, the size of the second region 2A may be larger than the size of the first region 1A.

Also, the area of the first region 1A of the elastic member 100 may be between 1% and 30% of the total area of the elastic member 100 . Specifically, the area of the first region 1A of the elastic member 100 may be 5% to 20% of the total area of the elastic member 100 . The area of the first region 1A of the elastic member 100 may be between 10% and 15% of the total area of the elastic member 100 .

When the area of the first region 1A of the elastic member 100 is less than 1% of the total area of the substrate 100, the folding and unfolding regions of the elastic member are repeated while folding and restoring the elastic member. cracks are generated at the interface between the elastic member 100 and the folding reliability of the elastic member 100 is deteriorated.

In addition, when the area of the first area 1A of the elastic member 100 exceeds 30% of the total area of the elastic member 100, the elastic member curls in the folding area of the display panel 200 when the elastic member is folded. can occur. As a result, when the user views the screen area, the visibility is reduced, and when the touch is driven, the screen of the touch area is imperfect due to the curl area, which may cause a touch malfunction.

Although the drawings show that the first region 1A is positioned at the central portion of the elastic member 100, embodiments are not limited thereto. That is, the first region 1A may be positioned at one end and end regions of the elastic member 100. As shown in FIG. That is, the first area 1A may be positioned at one end and end areas of the elastic member 100 such that the size of the first area 1A is asymmetrical.

FIG. 4 is a side view of the elastic member illustrating the elastic member after being folded.

Referring to FIG. 4, the elastic member 100 can be folded in one direction around the folding axis. Specifically, the first surfaces 1S may be folded in a direction facing each other along the folding axis.

As the elastic member 100 is folded in one direction, the elastic member 100 is formed with a first region 1A and a second region 2A. That is, the elastic member 100 has a folding area formed by folding the elastic member 100 in one direction and an unfolding area located at both ends of the folding area.

The folding region may be defined as a region having a curvature R, and the unfolding region may be defined as a region having no curvature R or a curvature close to zero.

3 and 4, the elastic member 100 is folded in one direction and formed in order of unfolding area, folding area, and unfolding area.

At least one of the first region 1A and the second region 2A is formed with a plurality of pattern parts to reduce and distribute the stress generated when the elastic member 100 is folded. The pattern unit will be described in detail below.

Meanwhile, FIG. 4 illustrates that the first surfaces 1S of the elastic member 100 are folded to face each other, but the embodiment is not limited to this, and the second surfaces 2S face each other. may be folded to

Hereinafter, elastic members according to various embodiments will be described in detail with reference to the drawings.

5 and 6 are top views of the elastic member according to the embodiment. 5 is a top view of the first surface 1S of the elastic member 100, and FIG. 6 is a top view of the second surface 2S of the elastic member 100. FIG.

5 and 6, the elastic member according to the embodiment may include a plurality of pattern parts PA. Specifically, the elastic member 100 may include a first pattern part PA1 disposed in the first area 1A.

The first pattern part PA1 is formed in a hole or groove shape.

Specifically, the first pattern part PA is formed in the shape of a hole passing through the first surface 1S and the second surface 2S of the elastic member, or formed on the first surface 1S or the second surface 2S. It is formed in a groove shape that

The first pattern part PA1 disposed in the first area 1A where the elastic member 100 is folded allows the elastic member 100 to be easily folded when the elastic member 100 is folded. be able to. Specifically, the thickness of the elastic member 1000 is reduced in the area where the elastic member 100 is folded by the first pattern part PA1, thereby reducing the compressive stress, so that the elastic member 100 can be easily folded. can.

On the other hand, in the first region 1A where the elastic member 100 is folded, compressive stress and tensile stress generated during folding and restoration of the elastic member 100 are greater than those in the second region 2A. During the process of folding and restoring 100, the first region 1A may undergo plastic deformation due to stress.

In the elastic member 1000 according to the embodiment, the shape of the first pattern portion PA1 arranged in the first region 1A is formed on the surface of the elastic member 1000 in order to minimize the plastic deformation that occurs in the first region 1A. The plastic deformation occurring in the first region 1A can be minimized by adjusting the direction of the formed surface roughness.

Specifically, the first pattern part PA1 is formed in a shape having a long direction LD and a short direction SD.

For example, referring to FIG. 5, the first pattern part PA1 is formed in a shape having a long direction LD and a short direction SD extending perpendicularly to the long direction LD.

A folding axis of the elastic member 100 is formed in a direction corresponding to the long direction LD of the first pattern part PA1.

The extension directions of the long direction LD and the short direction SD of the first pattern part PA1 are related to the surface roughness formed on the surface of the elastic member 100 .

A surface roughness is formed on the elastic member 100 . That is, at least one of the first surface 1S and the second surface 2S of the elastic member 100 is formed with surface roughness, so that the surface of the elastic member 100 may have surface roughness.

The surface roughness formed on the elastic member 100 is formed in a specific direction.

The surface roughness of the elastic member 100 is formed during the pretreatment process of the elastic member 100 .

Specifically, the elastic member 100 is subjected to a pretreatment process before forming the first pattern portion. For example, the elastic member 100 is subjected to a rolling process to reduce the thickness of the elastic member 100 and increase tensile strength and hardness before forming the first pattern portion in the first region 1A. For example, the elastic member 100 is subjected to a cold rolling process before forming the first pattern portion.

Referring to FIG. 7, a cold rolling process is performed on the elastic member 100 while passing the elastic member 100 between two rotating rolls at a low temperature. The elastic member 100 subjected to the cold rolling process may have a reduced thickness, and may have improved tensile strength and hardness. Therefore, when the elastic member 100 is applied to a flexible or foldable display device, folding characteristics can be improved.

At this time, the first surface 1S and the second surface 2S of the elastic member 100, which are in contact with the rollers, are subjected to pressure and/or friction applied to the elastic member 100 during the cold rolling process. surface roughness is formed on the Accordingly, the first surface 1S and the second surface 2S of the elastic member 100 have surface roughness formed in a specific direction.

That is, as shown in FIG. 8, the first surface 1S and the second surface 2S of the elastic member 100 are formed with a plurality of surface roughness SR extending from a starting point toward an end point. be done.

That is, the surface of the elastic member 100 is formed with surface roughness having a longitudinal direction in a specific direction. Here, the longitudinal direction SRD of the surface roughness is defined by the longitudinal direction of an imaginary line VL connecting the start point and the end point of the surface roughness. Alternatively, the longitudinal direction SRD of the surface roughness is defined as an average direction of multiple directions when the longitudinal direction SRD of the surface roughness includes similar multiple directions.

The longitudinal direction SRD of the surface roughness varies according to the rolling process. Specifically, the longitudinal direction SRD of the surface roughness is formed in a direction corresponding to the advancing direction RD of the roller. That is, the longitudinal direction SRD of the surface roughness is formed in the same direction as or in a direction close to the advancing direction RD of the roller.

Further, the longitudinal direction SRD of the surface roughness may be different from the vertical direction TD perpendicular to the traveling direction RD of the roller. That is, the longitudinal direction SRD of the surface roughness is perpendicular to or nearly perpendicular to the perpendicular direction TD.

The shape of the first pattern portion PA<b>1 described above varies depending on the longitudinal direction SRD of the surface roughness formed on the elastic member 100 .

Specifically, the first pattern portion PA1 formed in the first region 1A has a long direction LD and a short direction SD, and the long direction LD of the first pattern portion PA1 corresponds to the longitudinal direction of the surface roughness. Extends in a different direction than the SRD. That is, the long direction LD of the first pattern portion PA1 is not parallel to the longitudinal direction SRD of the surface roughness.

FIG. 9 is an enlarged view of a region of FIG. 5. As shown in FIG.

Referring to FIG. 9, the first pattern part PA1 may have a long direction LD and a short direction SD. The first pattern part PA1 may have a longitudinal direction in the long direction LD and a width direction in the short direction SD.

A long direction LD and a short direction SD of the first pattern part PA1 extend in directions perpendicular to each other. Specifically, the long direction LD of the first pattern part PA1 is defined to correspond to the folding axis direction FA of the elastic member 100, and the short direction SD of the first pattern part PA1 is defined to be the folding axis direction and the folding axis direction FA. It extends in a direction perpendicular to the long direction LD.

Referring to FIG. 9, the long direction LD of the first pattern part PA1 may be different from the longitudinal direction SRD of the surface roughness. That is, the long direction LD of the first pattern portion PA1 is not parallel to the longitudinal direction SRD of the surface roughness. That is, the angle θ between the long direction LD of the first pattern portion PA1 and the longitudinal direction SRD of the surface roughness may be greater than or equal to 50°. Specifically, an angle θ between the long direction LD of the first pattern portion PA1 and the longitudinal direction of the surface roughness may be 50° to 130°. That is, an acute angle θ1 between the long direction LD of the first pattern portion PA1 and the longitudinal direction of the surface roughness may be 50° to 90°, and the long direction LD of the first pattern portion PA1 and the surface roughness may have an acute angle θ1 of 50° to 90°. The longitudinal obtuse angle θ2 of the surface roughness can have a range of 90° to 130°.

Accordingly, the angle between the folding axial direction FA of the elastic member 100 and the longitudinal direction of the surface roughness may also be 50° to 130°.

More specifically, an angle θ between the long direction LD of the first pattern portion PA1 and the longitudinal direction SRD of the surface roughness may be 60° to 120°. More specifically, an angle θ between the long direction LD of the first pattern portion PA1 and the longitudinal direction of the surface roughness may be 70° to 110°. More specifically, an angle θ between the long direction LD of the first pattern part PA1 and the longitudinal direction of the surface roughness may be 80° to 100°.

That is, the long direction LD of the first pattern portion PA1 is formed closer to the vertical direction than the horizontal direction to the longitudinal direction SRD of the surface roughness.

When the rolling process is performed before forming the pattern part on the elastic member 100, surface roughness is formed on the surface of the elastic member 1000, and the elastic member 100 is separated from each other depending on the longitudinal direction of the surface roughness. They can have different physical properties.

For example, when the rolling process is performed in the second direction 2D of the elastic member 100, that is, when the rolling direction of the roller is in the second direction 2D of the elastic member 100, the first surface of the elastic member 100 Alternatively, the longitudinal direction of the surface roughness formed on the second surface is parallel to or close to the second direction 2D.

That is, the traveling direction RD of the roller is the same as or close to the second direction 2D, and the vertical direction TD is the same or close to the first direction 1D.

At this time, the elastic member 100 has different physical properties in the second direction 2D, which is similar to the traveling direction RD of the roller, and in the first direction 1D, which is similar to the vertical direction TD. Specifically, the elastic member 100 may have different elastic moduli and elastic moduli in the first direction 1D and the second direction 2D.

The elastic modulus E means the degree of deformation that occurs when an elastic material receives stress, and can be defined by Equation 1 below.

Equation 1

E (KN/mm ² )=σ/ε
(Here, σ means yield strength and ε means unit deformation.)
In addition, the elastic modulus means a deformation rate energy per unit volume required to increase the stress to the yield point, and can be defined by Equation 2 below.

Equation 2

即ち、前記数式２を参照すると、降伏強度が大きく、弾性係数が小さいほど弾力係数が大きいことをわかる。

That is, referring to Equation 2, it can be seen that the higher the yield strength and the lower the elastic modulus, the higher the elastic modulus.

The elastic member 100 that has undergone the cold rolling process has a smaller elastic modulus in the roller traveling direction RD than in the vertical direction TD. Accordingly, the elastic modulus calculated from the elastic modulus and the yield strength is larger in the traveling direction RD of the roller than in the vertical direction TD.

That is, after the first pattern portion is formed on the elastic member 100, the elastic member has a first remaining area SA1 in the traveling direction RD of the roller or the longitudinal direction of the elastic member 100 and a vertical direction TD or the longitudinal direction of the elastic member 100. A second residual area SA2 in the width direction remains.

At this time, the surface remaining after forming the first pattern part on the elastic member 100 can withstand the same stress for a long time as the surface in the advancing direction RD of the roller remains more.

Therefore, in the elastic member according to the embodiment, the long direction of the first pattern portion is formed in a direction different from the longitudinal direction of the roughness corresponding to or similar to the advancing direction RD of the roller, so that the remaining surface When the elastic member is folded, plastic deformation of the elastic member due to compressive or tensile stress can be minimized by leaving a large surface area of the roller in the traveling direction RD.

Thereby, the elastic member according to the embodiment can improve folding characteristics and folding reliability.

Hereinafter, the present invention will be described in more detail by measuring the yield strength, modulus of elasticity and modulus of elasticity of the elastic member according to the examples in the advancing direction and vertical direction of the roller. Such embodiments are merely provided as examples to further explain the present invention. Accordingly, the present invention is not limited to such examples.

The cold rolling process was performed while passing SUS 301EH between two rollers.

Subsequently, the yield strength, modulus of elasticity and modulus of elasticity of the SUS 301EH were measured in the advancing direction RD and the vertical direction TD of the roller.

After performing the cold rolling process in the same manner as in Example 1, except that SUS 301FH was used, the yield strength, elastic modulus, and elastic modulus of the SUS 301FH were measured in the advancing direction RD and the vertical direction TD of the roller. did.

After performing the cold rolling process in the same manner as in Example 1, except that SUS 316HN1 was used, the yield strength, elastic modulus, and elastic modulus of the SUS 316HN1 were measured in the rolling direction RD and vertical direction TD. did.

After the cold rolling process was performed in the same manner as in Example 1, except that SUS 316L was used, the yield strength, elastic modulus and elastic modulus of the SUS 316L were measured in the roller traveling direction RD and vertical direction TD. did.

After the cold rolling process was performed in the same manner as in Example 1 except that nickel silver was used, the yield strength of the nickel silver in the direction RD and the vertical direction TD of the roller was measured. , elastic modulus and elastic modulus were measured.
Referring to Table 1, it can be seen that the elastic members according to Examples 1 to 5 have different yield strengths, elastic moduli and elastic moduli according to the rolling direction, that is, the roller traveling direction RD and the vertical direction TD.

That is, the yield strengths of the elastic members according to Examples 1 to 5 may have similar magnitudes in the traveling direction RD and the vertical direction TD of the roller.

Further, it can be seen that the elastic moduli of Examples 1 to 5 are smaller in the direction of travel RD of the roller than in the vertical direction TD.

Also, it can be seen that the elastic coefficients of Examples 1 to 5 are larger in the direction of travel RD of the roller than in the vertical direction TD.

That is, it can be seen that the elastic modulus calculated from the yield strength and the elastic modulus is larger in the moving direction RD of the rollers, in which the elastic modulus is smaller, than in the vertical direction TD.

Therefore, in the elastic member, when the surface of the elastic member remaining after forming the pattern portion has a larger surface in the traveling direction RD of the roller than the surface in the vertical direction TD, it occurs when the elastic member is folded. It can be seen that the stress can be withstood for a longer time and the occurrence of plastic deformation is minimized.

Meanwhile, referring to FIG. 10, the elastic member according to another embodiment may further include a second pattern part PA2 disposed in the second region 2A.

The second pattern part PA2 is formed in a hole or groove shape.

Specifically, the second pattern part PA is formed in the shape of a hole passing through the first surface 1S and the second surface 2S of the elastic member, or formed on the first surface 1S or the second surface 2S. It is formed in a groove shape that

The second pattern part PA2 disposed in the second area 2A, which is an area where the elastic member 1000 is not folded, maintains physical characteristics similar to those of the first area 1A and the second area 2A. can be made

Specifically, the second pattern portion PA2 can reduce the difference in deformation due to heat from the first region 1A in which the first pattern portion PA1 is arranged. That is, when heat is applied to the elastic member 1000, pattern portions are formed in both the first region 1A and the second region 2A, so that heat is applied to the first region 1A and the second region 2A. Deformation difference can be relaxed. As a result, the elastic member 1000 can be prevented from bending or twisting.

In addition, the second pattern portion PA2 formed in the second region 2A can alleviate stress non-uniformity between the first region 1A and the second region 2A, thereby preventing bending of the elastic member.

In addition, when a panel or the like is adhered to the elastic member 1000 by the adhesive layer through the second pattern portion PA2 formed in the second region 2A, the adhesive material is mixed between the first pattern portion PA1 of the second region 2A and the second pattern portion PA2. Since the second pattern portions PA2 of the two regions 2A are filled together, the adhesive layer can be prevented from forming a step between the first region and the second region.

The second pattern part PA2 is formed in the same or similar shape as the second pattern part PA1. Specifically, the second pattern part PA2 is formed in a shape having a long direction and a short direction, and the long direction of the second pattern part PA1 and the long direction of the first pattern part PA1 are the same or similar to each other. The short direction of the second pattern part and the short direction of the first pattern part PA1 are extended in the same or similar directions.

As a result, even in the second region 2A, the long direction of the second pattern portion is formed in a direction different from the longitudinal direction of the surface roughness, and after the formation of the second pattern portion, the residual particles remain in the second region. The remaining area of the elastic member is greater on the surface in the direction of travel of the roller than on the surface in the vertical direction.

Therefore, when the elastic member 100 is folded, plastic deformation occurring in the second region can be prevented.

In addition, the long direction and the short direction of the pattern portions of the first region and the second region are made to be the same or similar to each other, thereby minimizing the difference in the elastic modulus between the first and second regions. When the elastic member is folded by the difference, it is possible to minimize bending or deformation of the elastic member.

Various embodiments of the elastic member formed of a single layer or multiple layers will now be described with reference to FIGS. 11 to 14. FIG.

11 to 14 are diagrams illustrating various cross-sectional views according to layer structures of various elastic members according to embodiments.

Referring to FIG. 11, the elastic member 100 is formed of a single layer. Specifically, the elastic member is formed of a single layer including the metal material described above.

In addition, the first pattern part PA1 and the second pattern part PA2 are formed to penetrate the elastic member 100 .

12 to 14, the elastic member 100 is formed of multiple layers.

Referring to FIG. 12, the elastic member 100 may include a first layer 110 and a second layer 120. As shown in FIG. The first layer 110 and the second layer 120 may be adhered by an adhesive layer 50 .

The first layer 110 and the second layer 120 may include different materials. For example, the first layer 110 may have a higher yield strength than the second layer 120 and the second layer 120 may have a higher thermal conductivity than the first layer 110 .

For example, the first layer 110 may contain SUS and the second layer 120 may contain copper. Accordingly, the second layer 120 may function as a heat dissipation layer.

Also, the first layer 110 and the second layer 120 may have different thicknesses. For example, the thickness of the first layer 110 may be greater than the thickness of the second layer 120 .

The first pattern part PA<b>1 and the second pattern part PA<b>2 are formed on the first layer 110 . That is, the first pattern part PA1 and the second pattern part PA2 are formed through the first layer 110 .

Referring to FIG. 13, the elastic member 100 may include a first layer 110 and a second layer 120. As shown in FIG. The first layer 110 and the second layer 120 may be placed in direct contact. For example, the first layer 110 and the second layer 120 may be manufactured using a clad method so as to be in direct contact with each other.

The first layer 110 and the second layer 120 may include different materials. For example, the first layer 110 may have a higher yield strength than the second layer 120 and the second layer 120 may have a higher thermal conductivity than the first layer 110 .

For example, the first layer 110 may contain SUS and the second layer 120 may contain copper. Accordingly, the second layer 120 may function as a heat dissipation layer.

Also, the first layer 110 and the second layer 120 may have different thicknesses. For example, the thickness of the first layer 110 may be less than the thickness of the second layer 120 .

The first pattern part PA<b>1 and the second pattern part PA<b>2 are formed on the second layer 120 . That is, the first pattern part PA1 and the second pattern part PA2 are formed through the second layer 120 .

Referring to FIG. 14, the elastic member 100 may include a first layer 110, a second layer 120 and a third layer . The first layer 110, the second layer 120 and the third layer 130 may be placed in direct contact. For example, the first layer 110, the second layer 120 and the third layer 130 may be manufactured using a clad method so as to be in direct contact with each other.

The first layer 110 may include a material different from that of the second layer 120 and the third layer 130 . For example, the first layer 110 has a higher yield strength than the second layer 120 and the third layer 130, and the second layer 120 and the third layer 130 have a higher thermal conductivity than the first layer 110. may

For example, the first layer 110 may include SUS, and the second layer 120 and the third layer 130 may include copper. Accordingly, the second layer 120 and the third layer 130 may function as heat dissipation layers.

Also, the first layer 110 may have a different thickness from that of the second layer 120 and the third layer 130 . For example, the thickness of the first layer 110 may be less than the thicknesses of the second layer 120 and the third layer 130 .

The first pattern part PA1 and the second pattern part PA2 are formed on the second layer 120 and the third layer 130, respectively. That is, the first pattern part PA1 and the second pattern part PA2 are formed through the second layer 120 and the third layer .

FIG. 15 is a drawing for explaining an example in which the elastic member according to the embodiment is applied.

Referring to FIG. 15, the elastic member according to the embodiment can be applied to a flexible or foldable display device for displaying a display.

For example, the elastic member according to the embodiment can be applied to flexible display devices such as mobile phones and tablets.

Such an elastic member can be applied to flexible display devices such as mobile phones, tablets, etc. that are flexible, bent or folded.

The elastic member is applied to flexible display devices such as mobile phones and tablets that are flexible, bent or folded, and improves the folding reliability of the display devices that are repeatedly folded or restored, thereby improving the reliability of the flexible display devices. can be improved.

The features, structures, effects, etc. described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to one embodiment. Also, the features, structures, effects, etc. illustrated in each embodiment can be combined or modified with respect to other embodiments by those who have ordinary knowledge in the field to which the embodiment belongs. Accordingly, all such combinations and variations are intended to be included within the scope of the present invention.

Although the above description has focused on the embodiment, this is merely an example and does not limit the present invention. Various modifications and applications not exemplified above are possible without departing from the characteristics. For example, each component specifically presented in the embodiment can be modified and implemented. All such variations and differences in application should be construed to fall within the scope of the invention as defined in the appended claims.

Claims (10)

An elastic member including a first region and a second region,
The elastic member has a surface roughness with a longitudinal direction,
wherein the first region is defined as a folding region and the second region is defined as an unfolding region;
a first pattern portion having a long direction and a short direction is formed in the first region of the elastic member;
The elastic member, wherein the longitudinal direction of the first pattern portion and the longitudinal direction of the surface roughness are different. The elastic member according to claim 1, wherein the longitudinal direction of the first pattern portion and the longitudinal direction of the surface roughness form an angle of 50° to 130°. The elastic member according to claim 1, wherein the folding axis direction of the elastic member and the longitudinal direction of the surface roughness form an angle of 50° to 130°. The elastic member includes a first direction close to the longitudinal direction of the surface roughness and a second direction close to the long direction of the first pattern portion,
The elastic member according to claim 1, wherein the modulus of elasticity in the first direction is smaller than the modulus of elasticity in the second direction. 4. The elastic member according to claim 3, wherein the modulus of elasticity in the first direction is greater than the modulus of elasticity in the second direction. further comprising a second pattern portion arranged in the second region;
The elastic member according to claim 1, wherein the long direction of the second pattern portion corresponds to the long direction of the first pattern portion. the elastic member includes a first layer and a second layer;
The elastic member according to claim 1, wherein the first pattern portion is formed on the first layer. 8. The elastic member of claim 7, further comprising an adhesive layer disposed between said first layer and said second layer. the elastic member includes a first layer, a second layer and a third layer;
the first layer is disposed between the second layer and the third layer;
The elastic member according to claim 1, wherein the first pattern portion is arranged on the second layer and the third layer. an elastic member according to any one of claims 1 to 9;
A display device comprising a panel disposed on the elastic member and including at least one panel of a display panel and a touch panel.

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